Advanced hot-gas control systems are being designed and tested with operating temperatures in excess of 3000° F. These operating temperatures preclude the use of many metals in the construction of the control systems. Refractory metals and their carbides, however, have very high melting points (e.g. TiC @ 3140° C., NbC @ 3500° C., ZrC @ 3540° C., TaC @ 3880° C., HfC @ 3890° C. and the mixed phase Ta4HfC5 @ 4215° C.), and could therefore be used in structural applications at temperatures in excess of 2000° C. (3632° F.). Moreover, refractory carbides exhibit unusually high oxidation resistance and can therefore be used in structural applications to temperatures exceeding that of refractory metals such as Re. Refractory carbides are also significantly lighter than refractory metals, with densities around 5-12 g/ccm (by way of comparison, Re, Ir and W have densities around 19-22 g/ccm).
Refractory metal and refractory metal carbide components are, however, difficult to produce using metallurgical processes such as casting, forming, machining, and joining. Because of these metals' high melting points, casting may be impractical, and therefore powder metallurgy is the primary process for producing refractory metal plates or barstock. This process is labor intensive, expensive, and has a long lead time, as components made via powder metallurgy must go through multiple processing steps and heat treatments, followed by costly and laborious machining processes that require special equipment.